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arXiv · hep-ph/9703265

Neutrino Flavor Conversion in Random Magnetic Fields

G. Domokos·S. Kovesi-Domokos
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Abstract

If massive neutrinos possess magnetic moments, a magnetic field can cause a spin flip. In the case of Dirac neutrinos the spin flip converts an active neutrino into a sterile one and vice versa. By contrast, if neutrinos are Majorana particles, a spin flip converts them to a neutrino of a different flavor. We examine the behavior of neutrinos in a random magnetic field as it occurs, for instance, in certain astronomical objects, such as an active galactic nucleus. Both Dirac and Majorana neutrinos behave ergodically: independently of their initial density matrix, they tend towards an equipartition of the helicity states. As a result, about half of the Dirac neutrinos produced becomes sterile. For Majorana neutrinos, there will be an approximate equipartition of flavors, independently of the production mechanism.

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G. Domokos, S. Kovesi-Domokos. 1997-03-18. Neutrino Flavor Conversion in Random Magnetic Fields. https://doi.org/10.1016/s0370-2693(97)00960-x

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